The cryptographic signature guarantees the file is safe to install and was not tampered
with in any way.

Mozilla is a nonprofit project and global community building a better internet. Mozilla Stumbler is an open-source wireless network scanner that collects GPS data for the Mozilla Location Service, our crowd-sourced location database. As you move around, the app "stumbles" upon new Wi-Fi networks and cell towers. The Mozilla Location Service combines these wireless network measurements to provide geolocation services for Firefox OS devices and other open source projects. For more information, visit our project page:
• location.services.mozilla.com

How to use Mozilla Stumbler
• The app stops/pauses automatically when you are not moving or your battery is low. (This feature works better on newer devices as they have better sensors).
• Go to un-stumbled areas (not covered in blue) to fill in the coverage map: location.services.mozilla.com/map
• Improve the accuracy of the service by stumbling in the blue areas.
• Try walking, biking, or driving new routes with Mozilla Stumbler every day!
• Start with major streets and intersections, then explore smaller streets.
• Your contributions will take a day to show up on the coverage map.